Many semiconductor devices include a dielectric layer between two conductors. If this dielectric is imperfect, leakage current across the dielectric may adversely affect device performance.
The invention relates to the use in semiconductor devices of a low-density, high-resistivity metal layer, preferably titanium nitride. Paired with a dielectric, the layer reduces leakage current across the dielectric.
It is known in the art that ionized metal plasma deposition of titanium nitride with no applied self-bias creates a low-density, high-resistivity titanium nitride (see Tanaka et al., “Properties of titanium nitride film deposited by ionized metal plasma source,” Journal of Vacuum Science Technology, March/April 1999), but the usefulness of this material in semiconductor devices according to the present invention has not been previously recognized.